2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 1998 John D. Polstra
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
32 #if !defined(IN_LIBDL) || defined(PIC)
35 * Linkage to services provided by the dynamic linker.
41 #include "namespace.h"
43 #include "un-namespace.h"
44 #include "libc_private.h"
45 #include "reentrant.h"
47 static char sorry[] = "Service unavailable";
49 void _rtld_thread_init(void *);
50 void _rtld_atfork_pre(int *);
51 void _rtld_atfork_post(int *);
54 * For ELF, the dynamic linker directly resolves references to its
55 * services to functions inside the dynamic linker itself. These
56 * weak-symbol stubs are necessary so that "ld" won't complain about
57 * undefined symbols. The stubs are executed only when the program is
58 * linked statically, or when a given service isn't implemented in the
59 * dynamic linker. They must return an error if called, and they must
60 * be weak symbols so that the dynamic linker can override them.
63 #pragma weak _rtld_error
65 _rtld_error(const char *fmt __unused, ...)
71 dladdr(const void *addr __unused, Dl_info *dlip __unused)
80 dlclose(void *handle __unused)
95 #pragma weak dllockinit
97 dllockinit(void *context,
98 void *(*lock_create)(void *context) __unused,
99 void (*rlock_acquire)(void *lock) __unused,
100 void (*wlock_acquire)(void *lock) __unused,
101 void (*lock_release)(void *lock) __unused,
102 void (*lock_destroy)(void *lock) __unused,
103 void (*context_destroy)(void *context) __unused)
106 if (context_destroy != NULL)
107 context_destroy(context);
112 dlopen(const char *name __unused, int mode __unused)
121 dlsym(void * __restrict handle __unused, const char * __restrict name __unused)
130 dlfunc(void * __restrict handle __unused, const char * __restrict name __unused)
139 dlvsym(void * __restrict handle __unused, const char * __restrict name __unused,
140 const char * __restrict version __unused)
149 dlinfo(void * __restrict handle __unused, int request __unused,
150 void * __restrict p __unused)
157 #pragma weak _rtld_thread_init
159 _rtld_thread_init(void *li __unused)
166 static pthread_once_t dl_phdr_info_once = PTHREAD_ONCE_INIT;
167 static struct dl_phdr_info phdr_info;
168 static mutex_t dl_phdr_info_lock = MUTEX_INITIALIZER;
171 dl_init_phdr_info(void)
176 for (auxp = __elf_aux_vector; auxp->a_type != AT_NULL; auxp++) {
177 switch (auxp->a_type) {
179 phdr_info.dlpi_addr = (Elf_Addr)auxp->a_un.a_ptr;
182 phdr_info.dlpi_name = (const char *)auxp->a_un.a_ptr;
185 phdr_info.dlpi_phdr =
186 (const Elf_Phdr *)auxp->a_un.a_ptr;
189 phdr_info.dlpi_phnum = (Elf_Half)auxp->a_un.a_val;
193 for (i = 0; i < phdr_info.dlpi_phnum; i++) {
194 if (phdr_info.dlpi_phdr[i].p_type == PT_TLS) {
195 phdr_info.dlpi_tls_modid = 1;
196 phdr_info.dlpi_tls_data =
197 (void*)phdr_info.dlpi_phdr[i].p_vaddr;
200 phdr_info.dlpi_adds = 1;
204 #pragma weak dl_iterate_phdr
206 dl_iterate_phdr(int (*callback)(struct dl_phdr_info *, size_t, void *) __unused,
212 __init_elf_aux_vector();
213 if (__elf_aux_vector == NULL)
215 _once(&dl_phdr_info_once, dl_init_phdr_info);
216 mutex_lock(&dl_phdr_info_lock);
217 ret = callback(&phdr_info, sizeof(phdr_info), data);
218 mutex_unlock(&dl_phdr_info_lock);
227 fdlopen(int fd __unused, int mode __unused)
234 #pragma weak _rtld_atfork_pre
236 _rtld_atfork_pre(int *locks __unused)
240 #pragma weak _rtld_atfork_post
242 _rtld_atfork_post(int *locks __unused)
246 #pragma weak _rtld_addr_phdr
248 _rtld_addr_phdr(const void *addr __unused,
249 struct dl_phdr_info *phdr_info_a __unused)
255 #pragma weak _rtld_get_stack_prot
257 _rtld_get_stack_prot(void)
260 return (PROT_EXEC | PROT_READ | PROT_WRITE);
263 #pragma weak _rtld_is_dlopened
265 _rtld_is_dlopened(void *arg __unused)
271 #endif /* !defined(IN_LIBDL) || defined(PIC) */